Environmental Monitoring 08/25/16

USEPA issued a modification to the Pompton Lakes Works facility RCRA permit on June 22, 2015 to remove mercury impacted soils and sediment from Pompton Lake. The remedy encompasses four areas consisting of approximately 40 acres. The areas identified in the permit modification include upland soils between Rotary Park and the lake, the lake bottom adjacent to Rotary Park, and the lake bottom at two downstream locations. A map depicting these areas is provided above.
A Corrective Measures Implementation (CMI) work plan which describes the means and methods upon which the remedy will be completed was approved by USEPA on April 22, 2016. Field activities associated with the remedy commenced in early June 2016. Work completed in 2016 consisted of the removal of soils in the Uplands Are and sediments in the Island Area and Lake Area A.
Environmental monitoring of surface water (turbidity), air (dust and mercury vapor), and noise is being conducted in accordance with the CMI work plan during the removal phases of the remediation program.
Download Monitor and Removal Area Detail View

Pompton Lake Study Area Activities

Sediment from the Delta Area is being removed “in the wet” using a hydraulic dredge. Positioning of the dredge is being performed using a real-time kinematic differential global positioning system (RTK DGPS) and Dredgepack system designed specifically for the hydraulic dredge. The contour surface is programmed into the Dredgepack system to provide the operator with a real-time display of removal depths/elevations.
Dredge management units (DMUs) have been established to guide the removal operations. After sediment removal is completed, an in-water post-dredging survey will be conducted by a New Jersey licensed firm to verify that the target elevations have been achieved.
A figure depicting the hydraulic dredge progress can be viewed by clicking on the link below.
Download DMU Progress Detail View
Water that comes into contact with the sediment being dredged (classified as “contact water”) is being managed in accordance with the approved New Jersey Pollutant Discharge Elimination System (NJPDES) Discharge to Surface Water (or BGR) and Treatment Works Approval (TWA) permits issued by the New Jersey Department of Environmental Protection (NJDEP).
Process water is being discharged back into the lake in accordance with the NJDEP-approved permits. Samples of the discharge water are collected for laboratory analysis. Concentrations are compared to the discharge limits established in the permits for compliance.
A summary of the discharge sample analytical results can be viewed by clicking on the link below.
Download Discharge Compliance Sample Results

Chemours is committed to sharing monitoring data (turbidity, dust, mercury vapor) collected during remedy implementation with the community. The graphs below contain data from the various monitoring locations around the project area.

1. Wind Monitoring

Click Image to Enlarge

2. PM10 Particulate (Dust) Monitoring

Click Image to Enlarge

3. Mercury Vapor Monitoring

Click Image to Enlarge

Comments

Based on a review of the mercury vapor data and site activities on this day (there were no excavation or load-out activities), it appears there was a mercury meter malfunction (due to continued heat and humidity) at the downwind monitoring station causing the elevated reading as shown on the graph. None of the other 15-minute average mercury readings collected during this monitoring event were above the instrument’s detection limit of 0.05 µg/m3 and were below the threshold level of 0.31 µg/m3.

4. Turbidity Monitoring

Click Image to Enlarge

Comments

It has been determined that there is a battery malfunction at the upstream monitoring location. A new battery is being procured and will be installed during the early portion of the week of August 29, 2016.